In recent years, many adjustable medical beds and general (long term care) beds have been available, allowing positional adjustment of the bottom sections thereof (i.e., angular/inclination adjustment of the adjustable bottom sections, so as to lift the back and knees) have been commercially available. Such beds have included versions designed to allow a user to lift and lower the back lifting portion (i.e., the adjustable section of the bed supporting the back) and the knee lifting portion (i.e., the adjustable section of the bed supporting the legs/knees), based on various action patterns. However, when the positions of bottom sections of such conventional beds are adjusted, the adjustment process is not always begun from the initial state, i.e., the state in which the sections of the bed are positioned so as to lie flat.
Actually, often, users start the adjustment process from a state wherein the back bottom section and the knee bottom section of the adjustable bed are already at an elevated position. Therefore, when conventional computer-controlled adjustable beds are adjusted according to a predetermined action pattern, starting from an already adjusted position (i.e., inclined position), it is necessary to first quickly adapt the positions of the bed sections to the action pattern.
U.S. Pat. No. 6,460,209 discloses a control means provided as a storing means for storing preferred positions of the back bottom member and knee bottom member, so that the back and knee bottom members can be controlled to travel to the positions stored in the storing means. However, in the '209 patent, the storing means only stores data concerning the final positions at which the back bottom member and the knee bottom member are inclined after having been controlled by the control means. The continuous positions and path (i.e, the intermediate positions) which the back bottom member and the knee bottom member are to pass before they reach the final positions are not stored in the control means.
Such conventional curves are illustrated in FIGS. 11 and 12, together with the path of travel, when the controller directs movement of the back bottom members to a desired final position. It has been found that when raising and lowering adjustable bed sections in conventional adjustable beds, users are frequently subjected to discomfort from pressure exerted on their abdominal sections, and slide relative to the bed during the movement process, all of which are undesirable in hospital and treatment settings. For example, patients that are recovering from abdominal surgery can be put at great risk of injury and pain if the adjustable bed upon which they are placed is adjusted in an improper manner that exerts harmful pressure upon their incision, operable area, etc.
Accordingly, it is an object of the present invention to solve these problems by providing a coordinative control method for the back and knee bottom sections of a bed or the like having back lifting and knee lifting functions, and computer program for implementing same. In particular, it is an object of the present invention to provide a method, and computer program for implementing same, operable to coordinatively raise and lower the back and knee bottom sections of an adjustable bed according to a predetermined action (preset action pattern) from any arbitrary position.